Reference ranges for lymphocyte subsets among healthy Hong Kong Chinese adults by single-platform flow cytometry

Race, age, sex, and environmental conditions have significant impacts on lymphocyte subset values. It is important to establish the local reference ranges from healthy and non-HIV-positive adults in the local population for clinical decision making. In this study, the reference ranges for lymphocyte subsets among Chinese adults were established by analysis by single-platform flow cytometry of the lymphocyte compositions of 273 healthy adult blood donors between 17 and 59 years of age. The 95% reference ranges for CD3(+) T cells, CD3(+) CD4(+) T helper cells, and CD3(+) CD8(+) T suppressor cells are 723 to 2,271 cells/μl, 396 to 1,309 cells/μl, and 224 to 1,014 cells/μl, respectively. The 95% reference ranges for CD19(+) B cells and CD56(+) NK cells are 118 to 645 cells/μl and 61 to 607 cells/μl, respectively. Significant gender and age differences in the lymphocyte subsets have been demonstrated. Our results have also shown that the T-lymphocyte compositions in Hong Kong Chinese were comparable to those of other Asian populations but were different from those of Caucasians.